The Employment Nondiscrimination Act would make it illegal for companies with more than 15 employees to discriminate against current or prospective employees on account of their sexual orientation or gender identity.

In the op-ed piece, titled "Workplace Equality Is Good for Business," Cook stresses that Apple strives to create a welcoming work environment where people can fully be themselves regardless of their ethnicity, race, gender or sexual orientation. When people are comfortable to be exactly who they are, Cook writes, they "have the comfort and confidence" to be the best version of themselves and to "do the best work of their lives."

Cook's piece reads in part:

Apple's antidiscrimination policy goes beyond the legal protections U.S. workers currently enjoy under federal law, most notably because we prohibit discrimination against Apple's gay, lesbian, bisexual and transgender employees. A bill now before the U.S. Senate would update those employment laws, at long last, to protect workers against discrimination based on sexual orientation and gender identity.

We urge senators to support the Employment Nondiscrimination Act, and we challenge the House of Representatives to bring it to the floor for a vote.

Apple has, of course, been a longtime and vocal supporter of gay rights, both in and outside of the workplace. You might recall that Apple this past February joined a number of companies in a collective effort to have California's Prop 8 deemed unconstitutional. Apple was also quick to praise the Supreme Court for overturning the Defense of Marriage Act (DOMA) this past June.